Stop-watch.



S. FISCHER. STOP WATCH. APPLIOATION FILED NOV.15,'1905.

Patented Dec. 8, 1908.

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s. FISCHER.

STOP WATCH.

APPLIOATION FILED NOV. 15, 1905.

906,21 2. I Patented Dec. 8, 1908.

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S. FISCHER. STOP WATCH. 'APrLmATIon-MLED nov. 15, 1905.

906,212. Patented Dec. 8, 1908.

3 SHEETS-SHEET 3. l iq-2 UNITEE SIGISMUND FISCHER, OF NEW YORK, N. Y.

STOP-WATGH.

no. eoe,212.

Application filed November 15, 1955.

To all whom it may concern:

Be it known that I, SIGISMUND Fisonnn, a citizen of the United States, residing in New York, in the borough of Manhattan, county and State of New York, have invented certain new and useful Improvements in Stop- Watches, of which the following is a specification.

This invention relates to certain improvements in stop-watches by which the operation of the stop-hand is accomplished in a reliable and effective manner by means of mechanism which can be readily applied to the top of the watch-movement and conveniently repaired when required; and the invention consists in the novel features of construction and combination of parts which will be fully described hereinafter and finally pointed out in the claims.

In the accompanying drawings, Figure 1 represents a top-view of my improved stopwatch, showing the stop-hand attachment in its initial osition or starting position, Fig. 2 is a sidee levation of the stop-hand attachment, drawn on a larger scale, Fig. 3 is a topview of the stop-hand attachment, showing it in position for setting the stop-hand in motion, Fig. 4 is a side-view of the mechanism, shown in Fig. 3, Fig. 5 is atop-view of the attachment, showing it in position for arresting the motion of the stophand, Fig. 6 is a longitudinal section on line 66, Fig. 5, Figs. 7 and 8 are respectively a detail top-view and a side-view of the main or fly-back lever of the stop-hand attachment, Figs. 9 and 10 are respectively a detail top-view and a side-view of the push-plate of the pawl-and-ratchet attachment and its spring, and Figs. 11 and 12 are respectively a detail vertical central section and a horizontal section on line 1212, Fig. 11, of the pinion and driving-disk on the arbor of the third wheel, and of the retaining disk of the pinion.

Similar letters of reference indicate corresponding parts in the different figures.

Referring to the drawings, a represents the stop-hand of my improved stop-watch and a the arbor of the same. The arbor a passes through a bore in the center-arbor of the movement and extends through the topplate I) of the movement and a bridge 6 on the same (it turning in an aperture a of the bridge 6). The arbor c of the stop-hand c also passes through the center-bore of a pinion 1), which turns freely around the arbor (t and which is continuously rotated by a driv- Specification of Letters Patent.

Patented Dec. 8, 1908.

Serial No. 287, i68.

ing-wheel of that is keyed to the arbor of the third wheel of the movement, saidarbor be ing extended through the top-plate and turning in bearings of the pillar-plate b and the bridge b The pinion p is supported in a fixed position relatively to the arbor a by means of a retaining-disk (Z having a centeropening through which a small hub (Z on the under-side of the pinion p extends, the lower end of said hub being slightly enlarged so as to be held by the retainin -disk (Z, while the.

latter is capable of being rotated on said hub. The retaining-disl-z d is placed into a recess d of the top-plate of the movement and secured thereto by two headed rivets d and a headed screw (1 so as to permit the pinion to rotate freely with or without the disk d around the arbor (0 while at the same time it is prevented from being moved in the direction of the axis of the arbor by the headed rivets and screw. To the upper side of the pinion p is attached a driving-disk c, which is provided with a beveled and minutely-toothed circumference. The driving-disk e is provided with a hole 0, outside of the pinion, for permitting a screw-driver to pass through the driving-disk c for the purpose of getting at the head of the screw (i and facilitating the screwing in or unscrewing of the same for placing the retaining-disk in position on or removing it from the top-plate of the movement. Above the toothed driving-disk e and in proximity thereto, is keyed to the stop-hand arbor c a larger disk-shaped plate f, the under-side of which is provided with a recess or depression corresponding in size with the size of the disk e. The circumference of the recess in the disk-plate is beveled and provided with minute teeth corresponding to the teeth of the driving-disk c. On the opposite side of the disk-platef and integral therewith is arranged a hub y, to which is attached a heartcam f said hub being held in position by a friction-springf which is attached at its outer end to the under-side of the bridge 5 and which presses by its free end on the hub f, the free end being provided with an eye for the passage of the stophand arbor (L as shown in Figs. 3 and 5. A. fly-back lever g is fulcrumed near one end to an arbor g which turns in bearings of both frame-plates of the movement in such a manner that its pointed end is located below the bridge and in proximity to the ll6tTtC2t1I1] while its opposite end is provided near the arbor with a depending con ical pin g having a shoulder g at its lower end, for properly retaining its spring 9 as shown in Fig. 8. The free end of the spring 9 acts on the shouldered pin g its opposite end being attached to the top-plate, said spring holding the fly-back lever g in its initial position. The fry-back lever g is provided at its middle portion with a pointed, forwardly-extending arm g having a pointed and step-shaped end for the purpose of engaging step-shaped cams w on the teeth to of a cam-wheel w, said arm g engaging freely the cam-steps or entering freely into the recesses formed between the teeth of the camwheel w, and serving thereby at the same time as an indirect check-pawl for a ratchetwheel w which is keyed to the arbor of the cam-wheel or riveted to the latter, said ratchet-wheel being operated in the usual manner by means of a push-pawl w which is located in proximity to the teeth of the ratchet-wheel so as to engage the same when said push-pawl is actuated by the crown of the watch-case. The arbor of the camwheel to and ratchet-wheel w is supported in bearings of the top-plate b and bridge 6 The number of teeth of the ratchet-wheel 'w is equal to the total number of camsteps W of the cam wheel. In the drawings the ratchet-wheel is shown with fifteen teeth, and the cam-wheel with five teeth with three cam-steps on each tooth, but the ratchetwheel may have a larger number of teeth, being a multiple of three, in which case the cam-wheel must be made with a corresponding number of cam-steps. As a consequence, the cam-wheel is checked by the lever just as many times as there are teeth on the ratchet-wheel, and this without a checkpawl. By doing away with a check-pawl, the number of parts and the friction are reduced, thus permitting an easier operation.

A fiat stop-spring s is located between the top-plate and the fly-back lever g and attached by a fastening-screw s at one end to the top-plate of the movement. The stop spring 8 is provided near the screw 8 with a heel 8 having a downwardly-bent projection s which engages in a recess in the top-plate so as to firmly hold the stop-spring in position thereon. The opposite or free end of the stop-spring s is provided with two diverging arms s of which the arm 8 extends under the disk-plate f, while the arm 8 is bent upwardly sidewise of the edge of the fly-back lever g so as to be depressed or released by the same as it is moved in one or the other direction, according as the pointed arm g of the fiy-back lever g is engaged by the step-shaped cams on the teeth of the cam-wheel w or by the recesses between the teeth of the cam-wheel. The spring-arm 8 serves for lifting the disk-plate f and the arbor of the stop-hand a away from the mi nutely-toothed driving-disk e on the pinion p as soon as the fiy-back lever g releases the upwardly-bent springarm 8 The bent arm 8 of the stop-spring s is so shaped that by the slightest shifting motion of the flyback lever g from its initial or starting position, the instant intermeshing of the diskplate f and driving-disk e and thereby the instant rotation of the disk-plate and the arbor of the stop-hand is produced. The bridge 5 has a step-shaped recess Z2 which forms a stop for the arm 8 of the stop-spring so as to limit the lifting of the disk-plate and allow the up or down motion or the so-called end-shake of the stop-hand arbor, said end-shake serving for the purpose of permitting the easy fly-back motion of the stophand.

At the end of the push-plate n is located a pin, the upper end of which extends through an opening, or slot in the top-plate and serves as the push-pawl w for the ratchet-wheel, while the lower end n is engaged by the stem of the crown, as shown in Figs. 2 and 6. The opposite end of the push-plate n has a recess 11 and a straight portion n that is engaged by the free end of a spring M. The recess 11, in the opposite end of the pushplate n moves along a stationary pin n at the under-side of the top-plate. The free end of the spring 71 presses on the straight portion n of the recessed end of the pushplate n until the push-plate is arrested by the stationary pin n The spring 12 serves for the purpose of returning the push-plate and the stem of the crown 0 so as to move the push-pawl clear of the teeth of the ratchetwheel. The spring a also serves to turn the push-plate slightly around the stationary pin n so that the pawl w is moved into the recesses between the teeth of the ratchetwheel by the depressions of the crown and its stem, due to the forward motion of the push-plate n and to the slight lateral motion imparted to it by the spring n The lateral play of the push-plate and its pawl is produced by resting the end of the spring n on the straight portion n beyond the stationary pin M, as shown clearly in Fig. 9.

The operation of my improved stop-watch is as follows: The stop-hand is held in its initial or starting position by the pointed end of the fly-back lever entering into the recess of the heart-cam, as shown in Fig. 1, so that the stop-hand points in the direction of the number 12 on the dial. In this position the disk-plate is out of mesh with the drivingdisk on the pinion driven from the arbor of the third wheel. By pushing the crown inwardly, its stem will move the push-plate and the push-pawl forward so as to turn the ratchet-wheel for one tooth and bring thereby the pointed arm of the fly-back lever against the highest step on the cam of the next adjacent tooth of the cam-wheel, as shown in Fig. 3. This moves the fly-back lever sufliciently so that its pointed end releases the heart-cam while its middle portion depresses the bent-up arms 5 of the stopspring and causes thereby the downward motion of the stop-spring; the spring f is thus permitted to force down the toothed dish-plate on the stop-hand arbor so that it is placed in mesh with the rotating drivingdislr e on the pinion p, as shown in Fig. l.

The intermeshing of the two disks produces the instant step-by-step motion of the stophand, for the reason that the same is placed in driving connection with the arbor of the third wheel of the movement. When it is desired to arrest the motion of the stop-hand, the crown is again pushed inwardly so that the push-pawl engages the next tooth ot' the ratchet-wheel and moves thereby the middle point of the tly-back lever on to the second or lowest step of the cam-tooth, which produces the partial inward motion of the lever, as shown in Fig. 5, so that it clears the bentup arm of the stop-spring and allows the arm 8" of the stop-spring to raise the disk-plate on the stop-hand arbor out of mesh with the driving-disk on the pinion, whereby the motion or the stop-hand is instantly interrupted. F or returning the stop-hand to its initial or starting position, the crown is again pushed inwardly, v hereby the ratchet wheel is turned for another tooth and the middle point of the fiy-back lever dropped into the recess between the lowest cam-step and the adjacent tooth of the cam-wheel, while the pointed end of the fiy-bacl: lever is returned into contact with the heart-cam so that the same, together with the disk-plate, the stophand arbor and the stop-hand, is returned into its initial or starting position, as shown in Fig. 1. In the dill erent positions 01' the middle point of the fly-back lever it presses against the highest and lowest cam-steps, and acts as an indirect check-pawl tor the ratchet-v. heel. It will thus be seen that the combined action of the pawl-and-ratchetmechanism, and the cam-wheel with its camshaped teeth, produces the movement of the fly-back-mechanism and stop-hand in the well-known three steps or periods, the starting, stopping and returning of the fly-backmechanism and stop-hand, in which the disk plate is active or in motion during the second period, when it is in mesh with the drivingdisk 011 the pinion, while it is inactive or at rest during the other two periods, when it is out of mesh with the driving-disk.

The advantages of the improved stopwatch are, firstly, the sudden and accurate stop of the stop-hand on any one of the graduations into which the minute-dial is divided; secondly, a gain in power, which is a most important item and which results from the fact that the stop-hand, being driven from the arbor oi the third wheel instead of from the usual fourth wheel, has about eight times as much power as the fourth wheel and leaves almost the full maimspring power to drive the watch movement; thirdly, the stop-hand arbor being driven directly lrom the arbor oi the third wheel, does not require the usual intermediate wheel between the fourth wheel and the pinion on the stop-hand arbor usually necessary in order to cause the stop-hand to move in the right direction; 'l'ourthly, the accomplishment of four different functions, namely, the starting, stopping and returning ot the stop-hand to its original position on the zero point or the dial, and the action of the same as an ineirect checlepawl for the ratchet-wheel, by means of one single fly-back lever instead of the numerous levers, pawls and springs heretofore employed for that purpose, which results in a saving in the number of parts, dispenses with the necessity of skilful adjustment, and permits the cheaper manufacture and easier repairs or the improved stop-watch.

Having thus described my invention, I. claim as new and desire to secure by Letters Patent:

1. In a stop-watch, the combination, with the arbor of the stop-hand, of an internallytoothed disk-plate keyed to the same and provided with a depression at its under-side, a toothed driving-disk adapted to mesh with the internally-toothed disleplate, a pinion keyed to said driving-disk and adapted to be driven from the arbor of the third wheel of the movement, said driving-disk and pinion being provided with a central bore for rotating freely around the arbor of the stop-hand, a retaining-disk connected with the hub of the pinion, headed rivets and a screw-stud on the top-plate for guiding the retaining-disk, and means for moving the disk-plate into or out of mesh with the toothed driving-disk.

2. In a stop-watch, the combination, with the stop-hand arbor, of a toothed drivingdisk provided with an aperture, a pinion on said driving-disk driven from the arbor of the third wheel of the movement, said drivingdisk and pinion being provided with a central bore for turning freely around the stophand arbor, a hub on the driving-pinion, a retaining-disk set into a recess of the top-plate and connected with said hub, and headed rivets and a screw-stud for holding the re taming-disk in the recess of the top-plate, said screw-stud being accessible through the aperture in said driving-disk for the insertion, removal and adjustment of the retaining-disk.

3. In a stop-watch, a fly-back lever pro vided with an arbor near one end and a conical pin near said arbor having a shoulder or rim at its lower end for engagement with its actuating-spring.

4. In a stop-watch, a ily-back lever provided with an arbor at one end, a rimmed and conical pin near said arbor, a tapering &

arm at the opposite end, and a pointed arm at the middle portion of the lever.

5. In a stop-watch, the combination, with the top-plate of the movement, of a stopspring for the fly-back lever, means for attaching it to the top-plate at one end, and branch-arms at the opposite end, one arm being bent-up for engagement with the flythe ratchet-wheel and a star-wheel on said ratchet-wheel, of a push-plate having a pushpawl at one end, and a shouldered and recessed portion at the opposite end, a stationary pin on the topplate for guiding said push-plate, and a spring engaging the shoulder of the push-plate.

8. In a stop-watch, the combination, with a ratchet-wheel and a star-wheel on said ratchet-wheel, of a push-plate having a pin at one end forming a push-pawl above and a push-pin below said plate, and a shouldered and recessed portion at its opposite end, a stem on the crown for engaging the push-pin, a stationary pin on the top-plate for guiding the recessed end of the push-plate, and a spring engaging the shouldered portion of the push-plate beyond the guide-pin and adapt ed to place the pawl in engagement with the teeth of the ratchet-wheel and returning the crown into normal position.

9. In a stop-watch, the combination, with a ratchet-wheel and a cam-wheel on said ratchet-wheel, said cam-wheel having teeth with three cam-steps on the same, of a spring-actuated fly-back lever actuated by said cam-wheel, and provided at its middle portion with a pointed arm engaging the cam-steps of the cam-wheel and acting as a check-pawl for the ratchet-wheel.

10. In a stop-watch, the combination,

' with a fulcrumed and spring-actuated flyback lever, of a stop-spring actuated by the same, said stop-spring having two arms, a straight one extending below the disk-plate, the other being bent-up for engagement with the fly-back lever, and a bridge provided with a shoulder forming a stop for the straight arm of the stop-spring for permitting the end-shake of the stop-hand arbor.

11. In a stop-watch, the combination, with the stop-hand arbor, of a driving-disk, a pinion on the same, said pinion being provided with an upset hub, a retaining-disk placed on said hub and adapted to rotate with the pinion or turn independently thereon, and means for holding said retaining-disk in position on the top-plate.

12. In a stop-watch, the combination, with the stop-hand arbor, of a driving-disk, a pinion on the same, means for driving said pinion and disk from the arbor of the third wheel, a retaining-disk placed loosely on the hub of the pinion, and means for holding the retaining-disk on the top-plate so as to permit the turning of the pinion with the retaining-disk or independently of the same.

In testimony, that I claim the foregoing as my invention, I have signed my name in presence of two subscribing witnesses.

SIGISMU ND FISCHER.

Witnesses:

PAUL GoEPEL, H. J. SUHRBIER. 

